Jack and lubricated bearing means therefor



May 9, 1950 E. s. FIELDS JACK AND LUBRICATED `BRING MEANS THEREFOR Filed Jan. 22, 194e INVENTOR Edward ,Silds' ',vd/M.'

ATTORNEYS Patented May 9, 1950 UNITED s TM ss .eM-ENT `To Ferca 2,506,634 vJACK AbfLUBarcATEpfE-ARNG MEANS yTHEREFOR YEdward-S. Fieldalvlorgantown, Va. Application .raiayiza 1946,1seia1rioj642l5b s claims. (ci.y zas-98) l The present invention relates to jacks and more especially to mine, roofor 'timber jacks.

It is among the objects of the invention yto provide ajack of the above category, which shall be largely of inexpensive tube, bar and plate stock easily assembled, with a standard type of antifriction'bearing, the moving'parts of which jack are completely venclosed and readily maintained packed with grease and relatively free from access of dust, dirt or grit and inherentlyf'protected against mechanical iujury, and whichthougho 'light construction, 'shall yet have adequate strength.

In the accompanying drawings in which are shown one or more of various possible embodiments of the several features of the invention,

Fig. 1 is a side elevation of the jack,

Fig. 2 is a view in longitudinal cross section on a larger scale, and with parts broken away, taken on line 2-2 of Fig. 1,

Fig. 3 is a View in transverse cross section, taken on line 3-3 of Fig. 2 and on a like scale, and

Fig. 4 is a transverse sectional view taken above the handle, of a slight modification.

Referring now to the drawings, the jack comi prises a tubular standard IU, desirably of round steel tubing, provided with the conventional handle loop II welded thereto. The standard is desirably welded as at I2a to a at base plate I2.

The standard mounts a precision type roller bearing R, the inner race I3 of which is welded to the upper end of the standard. The rollers I4 in roller cage I5 encompass the inner race I3, with the rollers riding upon the outwardly protruding ledge I3a of the inner race. The conical bore IIa of the outer race I6 rides on the rollers I4 and supports a cylindrical shell I1. To this end the shell has an inner peripheral shoulder I8, which rests upon said outer race I6 and the inner wall of the cylindrical shell I1 encompasses the outer cylindrical wall IBb of the outer race.

The shell I'I is formed as a unitary skirt of the nut I9, which latter has diametrically opposed operating handles 20 of bar stock welded thereto. To this end nut I9 may be telescoped into the upper end of the shell Il' and welded in place at 2| as shown, into a structure integral therewith.

Through the nut I9 extends the jack screw 22 which protrudes downward into the tubular standard I0 and carries the head H which desirably is of a piece of thick sheet metal stock 23 with the lateral downwardly bent flanks 24, em- ;bracing the socket 25 welded in place therebetween, into which the upper end of the jack screw is rigidly affixed as by soldering or welding.

"2 "Pr'eferably 'the lower 'eind i of 3 the A"skirt i I1 rigidly aflizedrtheretd or if desired madefas-'Lan integrale@ therewith# an armhis ,Zfsrroufnd- 'ing'the jack screw.` The roller bearing `abouttlie vjackscrew is thusjenelosedv in,l a case, the Alateral Wall of which isthef's'kirt Ilgthelow'er wall'th'e annulusZ v'andthe upper wall vth'ejnut I9. U The-casel isA readily packed *withgrease through `a grease nipple 2l in the side of the skirt and'p'referably a VIcaie.plate 2,8 'which' may jbewelded to 'tlieupper vpart of"the stan`dard between the roller bearing Rand the annulus `blocks the 'downward ilow of the grease.

In operation, after the jack is put in position, the handles 20 are turned, thereby rotating the nut I9 with its skirt IT, to entrain therewith the outer race IE about the roller bearing and to cause the jack screw 22 to rise and press the head I-I upward against the timber. 'Ihe lifting thrust is adequately transmitted and borne by the grease packed roller bearing R which transmits the thrust downwardly and radially inward to the standard Ill of steel tubing.

There is no likelihood of rapid wear or of jamming or :binding since the transmission case fully encloses and mechanically protects the movable parts and is adequately packed with grease at all times and no dust, dirt or grit enters the case. The parts move freely and with little friction on the roller bearing. Moreover the bearing of the jack screw in the nut I9 is inherently lubricated by grease entrained from the case in the upward movement. Therefore, the jack, though of relatively light weight, will give years of adequate service for withstanding relatively tremendous loads and with the need for no attention other than occasionally to replenish the grease through the nipple 21.

The device can be readily released from set position by reversing the direction of rotation of handles 20.

In the alternative embodiment of Fig. 4, the nut is provided with an offset handle comprising an elongated bar 2S headed at 30, passing through an aperture 3! in a rectangular lug 32 unitary with and protruding laterally from the nut I9'. The handle may be slid from one extreme to the other so as to afford greater leverage Where necessary or desirable.

As many changes could be made in the above construction, and many apparently widely different embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying i inner race having a flange supporting the lowerV edgs of the rollers of said cage and having an outer race overhanging said standard, a case coaxial with said standard, encompassing said roller bearing structure and dening a grease receptacle thereabout, said case comprising a nut having a cylindrical skirt rigid therewithvwithan inner shoulder resting upon said' outer race and an annulus rigid with the lower end of said skirt, and extending radially thereof nearly to the Vouter wall of said standard, a baille plate rigidi` with said ystandard between said kroller bearing and said Vannulus, the periphery of said baille plate extend ing nearly to the inner wall of said skirt, handles fon said nut, ajack screwrthrough said nut, encompassed by Said roller bearing and extending through said annulus into said tubular standard,

Aand a grease nipple in said skirt above said baffle plate.

2` A jack, comprising a tubular standard, a

, j ackscrew therethrough,abearinghaving an inner race mounted on the upper part of said standard,

a. bearing cage thereabout, an outer race about said cage, a case coaxial with the standard resting upon said outer race encompassing said bearing and dening a grease receptacle thereabout, means to prevent leakage of grease from said case and a nut threaded on said jack screw at the upper part of said case, and having opposed operating handle bars.

' 3. A jack, comprising av tubular standard, a bearing structure supported at its inner race upon the upper end thereof, a case defining a grease receptacle about said bearing structure and presenting a shoulder carried upon the outer race of 'j said bearing structure, a baille plate in said case rigid with said standard and below said bearing structure, and a jack screw through said case extending at its lower end into said tubular standard.

` EDWARD S. FIELDS.

REFERENCES CITED The following references are of recordintlie le of this patent: ix-

UNITED STATES PTEN TS Pasternack Y June 720, k194,4 

